One vertex per element, one color per generator, with an edge from x to x·s.
(1,2)(3,6)(4,5)(7,8)(9,10,14,20,15,19,28,37)(11,21,24,35,25,40,32,16)(12,26,13,18,29,17,31,38)(22,39,30,33,27,34,23,36)(9,11)(10,16)(12,27)(13,30)(14,32)(15,25)(17,36)(18,39)(19,35)(20,40)(21,37)(22,29)(23,31)(24,28)(26,33)(34,38) involution — undirected(2,5)(6,8)(9,12,28,31,15,29,14,13)(10,17,37,18,19,26,20,38)(11,22,32,23,25,27,24,30)(16,33,40,39,35,36,21,34)(9,13,14,29,15,31,28,12)(10,18,20,17,19,38,37,26)(11,23,24,22,25,30,32,27)(16,34,21,36,35,39,40,33)(1,3,4,7)(2,6,5,8)(10,19)(16,35)(17,26)(18,38)(20,37)(21,40)(33,36)(34,39)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.